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Author Topic: Greenland 2020-21 SMB (Snowfall & Melting) Year  (Read 10420 times)

gerontocrat

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Greenland 2020-21 SMB (Snowfall & Melting) Year
« on: September 05, 2020, 12:30:00 PM »
I am starting this thread so these posts conform to the DMI Greenland Year September to August as in their website http://polarportal.dk/en/greenland/surface-conditions/.

Also,I will plonk GRACE-FO data on overall Greenland Ice Sheet Mass here (when I get it).

The Greenland 2019-20 melting Season thread is staying open, as there will be many year end reports coming out in the next few months.

Here are the daily & cumulative graphs for 4 September.
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Greenland 2020-21 SMB (Snowfall & Melting) Year
« Reply #1 on: September 06, 2020, 12:12:07 PM »
Data from...
http://polarportal.dk/en/greenland/surface-conditions/
http://ensemblesrt3.dmi.dk/data/prudence/temp/PLA/PP_GSMB/

The new DMI year for SMB starts while the DMI keeps the old year for melt open. Too complicated for little me.

Data as at 5 Sep 2020.

Melt a respectable 7.4% of the surface area of Greenland.

Precipitation high(ish).
The result is a daily SMB gain of 2.2 GT.

Cumulative SMB gain for the year is 4.5 GT.

Melt may persist though reducing
A succession of lows bringing a mixture of rain and snow may well mean precipitation is high

SMB gains - maybe some large - in prospect.
_________________________________________________________________
Updates will be less frequent from now, depending on any  unusual SMB gains or lack of gains.
Click on images for full size view.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: Greenland 2020-21 SMB (Snowfall & Melting) Year
« Reply #2 on: September 13, 2020, 10:57:21 AM »
Data from...
http://polarportal.dk/en/greenland/surface-conditions/
http://ensemblesrt3.dmi.dk/data/prudence/temp/PLA/PP_GSMB/


Data as at 12 Sep 2020.

Melt has reduced to almost zero.

Precipitation quite low this week.

Cumulative SMB gain for the year is 13.4 GT, a little bit below average.

There may be a final blip of melt mid-week.
A succession of lows bringing a mixture of rain and snow may well mean precipitation is high.

SMB gains - maybe some large - in prospect.

Updates will be less frequent from now, depending on any  unusual SMB gains or lack of gains.
_________________________________________________________________
Click on images for full size view.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: Greenland 2020-21 SMB (Snowfall & Melting) Year
« Reply #3 on: September 16, 2020, 06:29:48 PM »
Data from...
http://polarportal.dk/en/greenland/surface-conditions/
http://ensemblesrt3.dmi.dk/data/prudence/temp/PLA/PP_GSMB/


Data as at 15 Sep 2020.

Melt did a small blip up to 1.15%.

Precipitation was low this week but on this day a big dump..

Cumulative SMB daily gain high at 4.4 GT, for the year 18.4 GT, a little bit below average.

There may be a final blip of melt today (Wednesday)
A succession of lows bringing a mixture of rain and snow may well mean precipitation is high.

SMB gains - maybe some large - in prospect.

Updates will be less frequent from now, depending on any  unusual SMB gains or lack of gains.
_________________________________________________________________
Click on images for full size view.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: Greenland 2020-21 SMB (Snowfall & Melting) Year
« Reply #4 on: September 18, 2020, 11:08:53 AM »
Data from...
http://polarportal.dk/en/greenland/surface-conditions/
http://ensemblesrt3.dmi.dk/data/prudence/temp/PLA/PP_GSMB/

Data as at 17 Sep 2020.

Melt did a small blip up to 2.3% on the 16th

Precipitation high in the last 2 days..

Cumulative SMB daily gain high at 5 GT on the 16th, 2Gt on the 17th, for the year 25.4 GT, almost up to average.

There may be some final blips of melt this month, but very small.
A succession of lows bringing a mixture of rain and snow may well mean precipitation is high.

SMB gains - maybe some large - in prospect.

Updates will be less frequent from now, depending on any  unusual SMB gains or lack of gains.
_________________________________________________________________
Click on images for full size.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: Greenland 2020-21 SMB (Snowfall & Melting) Year
« Reply #5 on: October 03, 2020, 01:03:04 PM »
Data from...
http://polarportal.dk/en/greenland/surface-conditions/
http://ensemblesrt3.dmi.dk/data/prudence/temp/PLA/PP_GSMB/

September 2020 to August 2021 Year


Data as at 2 October 2020.

Melt has petered out to almost zero
Precipitation variable

Cumulative SMB gain 53 GT, a bit below average.

There may be some final blips of melt this month. but very small.

Updates will be less frequent from now, depending on any  unusual SMB gains or lack of gains.
As it is somewhat boring at the moment, a gif is attached of melt and smb change to date.
_________________________________________________________________
Click on images for full size.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: Greenland 2020-21 SMB (Snowfall & Melting) Year
« Reply #6 on: October 16, 2020, 03:51:58 PM »
Data from...
http://polarportal.dk/en/greenland/surface-conditions/
http://ensemblesrt3.dmi.dk/data/prudence/temp/PLA/PP_GSMB/


data to 15 October

Melt has almost stopped. So instead here is a gif of daily SMB gain and cumulative SMB anomaly plus SMB and melt graphs.

Pretty much average snowfall so far.

"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: Greenland 2020-21 SMB (Snowfall & Melting) Year
« Reply #7 on: November 01, 2020, 07:27:30 PM »
Data from...
http://polarportal.dk/en/greenland/surface-conditions/
http://ensemblesrt3.dmi.dk/data/prudence/temp/PLA/PP_GSMB/


data to 31 October

No melt since 21 October. So instead here is a gif of daily SMB gain and cumulative SMB anomaly plus SMB and melt graphs.

Pretty much average snowfall so far.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: Greenland 2020-21 SMB (Snowfall & Melting) Year
« Reply #8 on: November 11, 2020, 03:28:30 PM »
And here is the September graph of SMB change (from DMI), Greenland mass change (from GRACE-FO), and gross mass loss from calving and glacial melt.

The data basically says Greenland fell asleep in September.

"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: Greenland 2020-21 SMB (Snowfall & Melting) Year
« Reply #9 on: December 02, 2020, 04:22:41 PM »
http://polarportal.dk/en/greenland/surface-conditions/
http://ensemblesrt3.dmi.dk/data/prudence/temp/PLA/PP_GSMB/

Greenland snowfall so far this year is boringly average.
Nothing remarkable about mass loss either, and the data is late in arriving.

Only posting this to keep the thread alive.

Don't bother with the gif unless you have a decent internet connection and are bored (it's large).
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: Greenland 2020-21 SMB (Snowfall & Melting) Year
« Reply #10 on: December 07, 2020, 06:23:32 PM »
Germany has put some more GRACE-FO ice-sheet data up @ ftp://isdcftp.gfz-potsdam.de/grace-fo/GravIS/GFZ/Level-3/ICE/

It's always a bit later (to mid Sept 20) than the text files from JPL/PO-DACC, but it's down to basin level.

Looks like a small overall ice mass gain in September, with mass loss in the south and mass gain in the north.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: Greenland 2020-21 SMB (Snowfall & Melting) Year
« Reply #11 on: December 22, 2020, 04:10:45 PM »
The average year remains somewhat average

Note that the DMI melt and SMB graphs have daily data up to one day ago, BUT...

The graphs that combine DMI and GRACE-FO data use monthly data mid-month to mid-month. This is because for some reason (unknown to me) the GRACE-FO data is cumulative data to midmonth. So to make a comparison the DMI data has to be mid-month to mid-month.

Note also the GRACE-FO data is always one to two months in arrears (at best).

Final Note - the GIS cumulative mass loss summary GRACE data from JPL is considerably higher than the mass  loss data by basin provided by the GFZ German Research Centre for Geosciences in Potsdam. Some time ago I pointed this out to GFZ who said it would be looked at. Nothing back.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: Greenland 2020-21 SMB (Snowfall & Melting) Year
« Reply #12 on: January 25, 2021, 01:28:41 PM »
http://polarportal.dk/en/greenland/surface-conditions/
http://ensemblesrt3.dmi.dk/data/prudence/temp/PLA/PP_GSMB/

Greenland snowfall so far this year is still boringly average. However, a closer look at the accumulated snowfall anomaly map is of interest (image attached).
Overall the anomaly is pretty much zero, but there are strong positive anomalies (i.e. above average snowfall) on the west coast, and especially on the SW coast and southern tip of greenland. Meanwhile there are negative anomalies (i.e. below average snowfall) on the east and north coast.

I also attach the graph of SMB, and graphs that combine DMI and GRACE-FO data using monthly data mid-month to mid-month. This is because for some reason (unknown to me) the GRACE-FO data is cumulative data to midmonth. So to make a comparison the DMI data has to be mid-month to mid-month.

"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: Greenland 2020-21 SMB (Snowfall & Melting) Year
« Reply #13 on: February 17, 2021, 03:43:41 PM »
http://polarportal.dk/en/greenland/surface-conditions/
http://ensemblesrt3.dmi.dk/data/prudence/temp/PLA/PP_GSMB/

Greenland snowfall so far this year is still boringly average. However, a closer look at the accumulated snowfall anomaly map is of interest (image attached).
Overall the anomaly is pretty much zero, but there are strong positive anomalies (i.e. above average snowfall) on the west coast, and especially on the SW coast and southern tip of greenland. Meanwhile there are negative anomalies (i.e. below average snowfall) on the east and north coast.

I also attach the graph of SMB
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

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Re: Greenland 2020-21 SMB (Snowfall & Melting) Year
« Reply #14 on: February 17, 2021, 09:16:55 PM »
So more than average snowfall in areas were the microclimate has already shifted to warmer and wetter and less snowfall where less change has occurred. Somehow This fails to reassure me about the future. 

gerontocrat

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Re: Greenland 2020-21 SMB (Snowfall & Melting) Year
« Reply #15 on: February 19, 2021, 01:47:16 PM »
Here is the latest GRACE-FO GIS data from Germany - to November 2020. Always one month behind the summary data from the summary data from JPL's PO.DACC system.

It is winter - melting of glaciers continues but overall Mass increases slightly (see next post).

"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: Greenland 2020-21 SMB (Snowfall & Melting) Year
« Reply #16 on: February 19, 2021, 01:56:49 PM »
I attach the graph that shows SMB, Mass loss from glaciers melting, and net mass loss/gain.
i.e. the SMB data from DMI is combined with GRACE-FO GIS Mass data.

The data is to mid Dec 20 for GIS mass and mid-Feb20 for SMB data.

SMB gain is currently greater than mass loss from glacial melting (at this time of year mainly from marine-terminating glaciers), hence overall mass loss gains slightly.

Some climate models tell us that as AGW continues SMB gain may increase in winter as warmer wetter air increases snowfall but eventually annual SMB gain will decline and could be -ve by mid-Century. On average currently annual SMB gain runs at an average a bit above 360 GT.

As usual click image to enlarge
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)